This invention relates generally to automated irrigation systems and, more particularly, to systems for the control of irrigation devices, such as valves, pumps and rotors. Water valves and pumps are used to control the flow of irrigation water through a variety of water dispensing devices, including rotors. Rotors irrigate by throwing a jet or spray of water that is rotated about a generally vertical axis. Rotors are typically enclosed in a protective housing, and a rotating nozzle pops up from the top of the housing during desired irrigation times. Rotors are supplied with water from water supply lines that are usually installed below ground and are typically actuated by electric solenoid-controlled valves. Rotation of the nozzle may be effected by a self-contained water turbine and a reduction gear mechanism, or the nozzle may be of the impact-arm type, which utilizes the angular momentum of a spring-loaded oscillating arm to rotate the nozzle in small angular increments through a desired arc, or continuously through a full circle of rotation.
Valves, pumps and rotors are used in a wide variety of irrigation applications, from residential and commercial landscapes to golf course and agricultural irrigation. The application to golf course irrigation is mentioned here by way of example, but as the description of the invention proceeds it will be understood that the principles described are equally applicable to other types irrigation environments. A common feature of underground irrigation systems is that control wires must be run from a controller to each solenoid valve and pump that controls the flow of water to a sprinkler or group of sprinklers. Control wires to the valves, pumps and rotors are typically buried below ground, often in the same trenches used to run supply pipes to the valves. Control systems vary from simple multi-station timers to complex computer-based controllers.
The advantages of a wireless rotor, using a battery to control the solenoid valve, have been recognized by others. For example, U.S. Pat. No. 4,626,984 to Unruh, U.S. Pat. No. 5,813,655 to Pinchott et al., and U.S. Pat. No. 4,962,522 to Marian, broadly suggest some features of a wireless rotor. None of these patents, however, suggest all the features of the present invention, which are summarized below.